These charts have been designed using a rainfall intensity of 50 mm / hour.

STORMDRAIN Laid Level

Channel Run

SD250

SD350

SD400

SD500

30 lin metre

3024 m2

7848 m2

19008 m2

42264 m2

50 lin metre

2520 m2

6552 m2

16416 m2

37008 m2

100 lin metre

1872 m2

5040 m2

12960 m2

29880 m2

125 lin metre

1728 m2

4680 m2

12024 m2

27864 m2

150 lin metre

1656 m2

4464 m2

11160 m2

26064 m2

175 lin metre

1512 m2

4104 m2

10584 m2

24624 m2

200 lin metre

1440 m2

3888 m2

10008 m2

23400 m2

As a function of its size STORMDRAIN can be laid level. To use the above table the downstream outlet must have a free discharge.

STORMDRAIN Laid to Gradient

Gradient

SD250

SD350

SD400

SD500

1/50

170 l/sec

400 l/sec

830 l/sec

1555 l/sec

1/100

120 l/sec

280 l/sec

600 l/sec

1100 l/sec

1/200

85 l/sec

200 l/sec

420 l/sec

750 l/sec

1/300

70 l/sec

160 l/sec

340 l/sec

600 l/sec

1/400

60 l/sec

140 l/sec

290 l/sec

560 l/sec

1/500

55 l/sec

130 l/sec

265 l/sec

500 l/sec

1/1000

38 l/sec

90 l/sec

185 l/sec

340 l/sec

To calculate channel size required at the downstream outlet: Multiply the maximum drained area (A) by the rainfall intensity (I) and divide by the number of seconds in an hour (3600).Therefore A*I/3600 =V. V= velocity in litres/sec

STORMDRAIN Laid Level

Channel Run

SD250

SD350

SD400

SD500

30 lin metre

42 l/sec

109 l/sec

264 l/sec

587 l/sec

50 lin metre

35 l/sec

91 l/sec

228 l/sec

514 l/sec

100 lin metre

26 l/sec

70 l/sec

180 l/sec

415 l/sec

125 lin metre

24 l/sec

65 l/sec

167 l/sec

387 l/sec

150 lin metre

23 l/sec

62 l/sec

155 l/sec

362 l/sec

175 lin metre

21 l/sec

57 l/sec

147 l/sec

342 l/sec

200 lin metre

20 l/sec

54 l/sec

139 l/sec

325 l/sec

As a function of its size STORMDRAIN can be laid level. To use the above table the downstream outlet must have a free discharge.